According to one source, the average equity fund investor earned 16.4 percent.

According to a Strategic Insights news release, it was diversification into international funds that helped last year's equity investors make money.

"Investors and their financial advisers are increasingly focused on prudent diversification," commented Avi Nachmany, Strategic Insight's Director of Research, in the news release. "Rapid growth of funds-of-funds and other pre-packaged allocation programs such as mutual fund "wraps," atypical investments in bond funds in the face of the flat yield curve lately, and the extraordinary interest in international funds are just a few manifestations."

Last year, assets in all types of U.S. registered mutual funds totaled over $11 trillion. Here's an overview of where those assets were held:

One of last year's hot investments not to be overlooked was a fund-of-funds. These investments carry more layers of expenses then traditional mutual funds but even so, are picking up assets. In 2006, money flows into them was up 35% over 2005.